SATELLITEGALAXY
Satellite galaxy
A satellite galaxy orbits a larger galaxy due to gravitational attraction. Although a galaxy is made of a large number of objects which are not connected to each other, it has a center of mass, which represents a weighted average of the positions of each component object. This is similar to how an everyday object has a center of mass which is the weighted average of the positions of all its component atoms.The above text is a snippet from Wikipedia: Satellite galaxy
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